Genetic improvement of a neglected and underutilised oilseed crop: sesame (Sesamum indicum L.) through mutation breeding.

Sesame (Sesamum indicum L.) also known as Queen of oilseeds is being cultivated worldwide for its oil content for nutritional and medicinal value. Low productivity is one of the major constraints of sesame cultivation. Systematic efforts are made using induced mutagenesis to increase its productivity and realize earliness and alteration in genetic architecture. Sodium Azide was used as a chemical mutagen in the present study. Nine sesame varieties viz., TMV 3, TMV 4, TMV 5, TMV 6, TMV (Sv) 7, CO 1, VRI 1, VRI(Sv) 2 and Paiyur 1 released from Tamil Nadu Agricultural University, Coimbatore, India were subjected to mutation at three different concentrations of Sodium Azide viz., 5 mM, 10 mM and 15 mM. An extra early mutant that matured on 70 DAS was identified in M₄ generation of TMV 5 at 15 mM. This mutant (TVS 1401) was forwarded to subsequent generations with confirmed earliness. After confirming the superior performance of the mutant TVS 1401 for yield attributes in station trials, it was evaluated in MLT for two seasons. During Rabi 2017 MLT, it recorded 521 kg/ha of seed yield with the duration of 72 days. During Kharif 2018, it recorded 683 kg/ha of seed yield which was 21.96% higher yield than the popular check TMV 7 and matured 16 days earlier. This extra early mutant has white seed coat colour with 1000 seed weight of 3.22 g. Dissection of fatty acid profile of this mutant also confirmed its superiority. Distinctness of TVS1401 in molecular level was also established through RAPD markers viz., OPC03₅₅₀ and OPA04₅₅₀. [ABSTRACT FROM AUTHOR]